Support for the Ruby 2.4 series has ended. See here for reference.
This class works in conjunction with Psych::Parser
to build an in-memory parse tree that represents a YAML document.
parser = Psych::Parser.new Psych::TreeBuilder.new parser.parse('--- foo') tree = parser.handler.root
See Psych::Handler
for documentation on the event methods used in this class.
Create a new TreeBuilder
instance
# File psych/lib/psych/tree_builder.rb, line 22 def initialize @stack = [] @last = nil @root = nil end
# File psych/lib/psych/tree_builder.rb, line 81 def alias anchor @last.children << Nodes::Alias.new(anchor) end
Handles end_document
events with version
, tag_directives
, and implicit
styling.
See Psych::Handler#start_document
# File psych/lib/psych/tree_builder.rb, line 61 def end_document implicit_end = !streaming? @last.implicit_end = implicit_end pop end
# File psych/lib/psych/tree_builder.rb, line 71 def end_stream pop end
# File psych/lib/psych/tree_builder.rb, line 75 def scalar value, anchor, tag, plain, quoted, style s = Nodes::Scalar.new(value,anchor,tag,plain,quoted,style) @last.children << s s end
Handles start_document
events with version
, tag_directives
, and implicit
styling.
See Psych::Handler#start_document
# File psych/lib/psych/tree_builder.rb, line 50 def start_document version, tag_directives, implicit n = Nodes::Document.new version, tag_directives, implicit @last.children << n push n end